[问题现象] 开发同事反馈有应用在21:00-22:00之间出现大量超时报错. [问题分析] 1. 从DB服务器慢查询指标来看,18:00后有大量的慢查询,累计产生了约9000条慢查询 2. 测试直接执行慢查询SQL语句,并没有发现性能问题 3.当时DBA同事在排障现场看到了线程执行时等待Writing to net. 之前我们碰到过大量Writing to net等待的情况,通常是DB服务器网卡流量打满导致.但这次从DB服务器网卡流量上看,并没有打满,而且比较平稳. 从QPS和threads_

原文地址:https://www.javacodegeeks.com/2015/04/spring-enable-annotation-writing-a-custom-enable-annotation.html Spring provides a range of annotations with names starting with Enable*, these annotations in essence enable certain Spring managed features t

Writing to a MySQL database from SSIS 出处  :  http://blogs.msdn.com/b/mattm/archive/2009/01/07/writing-to-a-mysql-database-from-ssis.aspx Matt Masson - MSFT  7 Jan 2009 8:32 PM  16 A couple of users reported being unable to use the ADO.NET destination

最近花了一些时间看了这本书,书名是 <Writing Clean Code ── Microsoft Techniques for Developing Bug-free C Programs> 这里主要总结了一些里面的编程思想. 为空语句加上NULL 当需要使用空语句的时候,最好写上NULL, 比如: if (music_on()) NULL; else turn_it_on(); 参数类型相同的问题 如果函数中两个参数的类型相同,如果用户调用这个函数时错误替换了参数的顺序,就会出现问题.

Java.io.IOException: Error writing to server异常:我测试500个并发时,系统没有问题:可当我把线程数加到800时,就出现错误了,在"查看结果树"中,打开出错的请求,看到如下异常: java.io.IOException: Error writing to serverat sun.reflect.GeneratedConstructorAccessor24.newInstance(Unknown Source)at sun.reflect.D

问题描述: 严重: IOException while loading persisted sessions: java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: com.sh.rgsoft.blogonline.bean.Blog java.io.WriteAbortedException: writing aborted; java.io.NotSerializableExcept

Philosophy Markdown is intended to be as easy-to-read and easy-to-write as is feasible.Readability, however, is emphasized above all else. A Markdown-formatted document should be publishable as-is, as plain text, without looking like it's been marked

汇总了一下这本小书前两部分的内容: 翻译<Writing Idiomatic Python>(一):if语句.for循环 翻译<Writing Idiomatic Python>(二):函数.异常 翻译<Writing Idiomatic Python>(三):变量.字符串.列表 翻译<Writing Idiomatic Python>(四):字典.集合.元组 翻译<Writing Idiomatic Python>(五):类.上下文管理器.生成

原书参考:http://www.jeffknupp.com/blog/2012/10/04/writing-idiomatic-python/ 上一篇:翻译<Writing Idiomatic Python>(四):字典.集合.元组 2.7 类 2.7.1 用isinstance函数检查一个对象的类型 许多新手在接触Python之后会产生一种“Python中没有类型”的错觉.当然Python的对象是有类型的,并且还会发生类型错误.比如,对一个int型对象和一个string型的对象使用+操作就会

原书参考:http://www.jeffknupp.com/blog/2012/10/04/writing-idiomatic-python/ 上一篇:翻译<Writing Idiomatic Python>(三):变量.字符串.列表 下一篇:翻译<Writing Idiomatic Python>(五):类.上下文管理器.生成器 2.4 字典 2.4.1 用字典实现switch...case 和其他许多语言不一样,Python不支持switch...case.switch通常用来

原书参考:http://www.jeffknupp.com/blog/2012/10/04/writing-idiomatic-python/ 上一篇:翻译<Writing Idiomatic Python>(二):函数.异常 下一篇:翻译<Writing Idiomatic Python>(四):字典.集合.元组 2.1 变量 2.1.1 对多个变量要赋同一个值时,使用链式赋值让语句变得简明 Python支持链式赋值使多个变量可以在一次链式赋值中被设置为同一个值,这使得语句更加简

catalog . Comparison of parser generators . Writing a simple lexer in PHP . phc . JLexPHP: A PHP Lexer(xx.lex.php) Created By Java By x.lex File Input . JFlex . JLex: A Lexical Analyzer Generator for Java . PhpParser 0. Comparison of parser generator

Tips for writing a paper 1. Tips for Paper Writing 2.• Before you write a paper • When you are writing a paper • The expression 3.Before you start writing a paper • State your Contribution • Organize your paper structure, See Everything as a Facet on

C. Writing Code time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output Programmers working on a large project have just received a task to write exactly m lines of code. There are n programmers w

Introduction A common requirement is to have applications share data with other programs. Although there are interfaces available to work with, for example, Microsoft Excel data files, this approach is generally complex, involves a fair amount of ove

Setting Up <script src="js/jquery-1.9.1.min.js"></script> <script src="js/jquery.hello-world.js"></script> The jQuery Plugin Structure (function($) { $.fn.helloWorld = function() { // Future home of "Hello,

Below is the example to write file on client in Oracle Forms 10g with webutil library package.Note:  Webutil library must be attached to the form.DECLAREv_dir VARCHAR2(250) := 'c:\temp';ft_tempfile CLIENT_TEXT_IO.FILE_TYPE;beginft_tempfile := CLIENT_

Error writing file‘frm‘(Errcode: 28)   mysql出现这个错误,表示磁盘已经满了,该增加容量了.

Free and open source tools for doc generation: the JSDoc Toolkit (http://code.google.com/p/jsdoc-toolkit/) and YUIDoc (http://yuilibrary.com/projects/yuidoc). Process of generating API documentation • Writing specially formatted code blocks • Running

开篇废话 这是在美国Amazon上评价很不错的一本书,其实严格来说这可能不算书,而是一本小册子.就像书名一样,里面的内容主要是用一些例子讲述地道的Python的代码是怎样写的.书中把很多例子用不良风格和地道Python写法作对比,内容覆盖谈不上很全,但是每一条都很有代表性.总体而言非常适合新手,同时里面有些条目老手看了或许也会有豁然开朗的感觉.作者Jeff Knupp曾在全球最牛B的高盛和其他银行里做过金融系统开发,在北美Python社区里也很有活跃度. 自己用Python也有些年头了,做过一年

原书参考:http://www.jeffknupp.com/blog/2012/10/04/writing-idiomatic-python/ 上一篇:翻译<Writing Idiomatic Python>(一):if语句.for循环 下一篇:翻译<Writing Idiomatic Python>(三):变量.字符串.列表 1.3 函数 1.3.1 避免使用可变对象作为函数参数的默认值 当Python解释器遇到一个函数定义的时 候,如果参数里有默认值,会求值来决定默认的参数值.